Procedure Megger Test. [PDF]

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Megger Test Procedures The purpose megger test To determine the insulation resistance of an electrical equipment is essential to determine whether the equipment can be operated safely. In general if it will operate equipment in an electricity-like panels, generators, transformers and motors, you should first check the insulation prisoners, no matter whether new or long TSB tool dipakai.Untuk not use Megger to measure the insulation resistance (Mega Ohm Meter). Isolation that question is part-voltage isolation between the voltage and the parts that do not like the body voltage / ground. 1. Megger same measurement principle with ohm meter, which gives the voltage of the measuring instrument to the isolation of equipment, and because the value of the insulation resistance is quite high, the required voltage is high enough anyway so that current can flow. Voltage measurements are used depending on the working voltage of the device to be measured. Insulation test voltage to be diubah2 depending on the class of insulation used as: a. Measure the voltage of 500 Volt to 500 Volt voltage circuit below b. Voltage 1000 Volt for measuring voltage circuit below 1000 Volt c. Voltage 2500 Volt for measuring voltage circuit below 2500 Volt d. Voltage 5000 Volt for measuring circuit voltage 5000 Volt and above As for the standard price of minimum insulation resistance measurement results of a device can be calculated using the formula approach: ( 1000 . U ) R = ————— ∙ U ∙ 2,5 Q R



= Minimum insulation resistance.



U



= working voltage.



Q



= Voltage Megger.



1000 = Numbers remain. 2,5



= Safety Factor (when new).



examples: Measurements using a "Megger" with a DC voltage of 500 Volt to include a safety factor (2.5), when the working voltage of 400 V, then: ( 1000 . U )



R = —————-------- ∙ U ∙ 2,5 Q (1000 . 400) R = —————— . 400 . 2,5 = 0,80 MΩ. 500 2. Things that need attention / requirements before executing the test is: a. Tools that measure must be clean and dry b. Tools that measure must be free voltage AC / DC or the induced voltage, because the voltage will affect the measuring results c. Make sure the cable / busbar is not connected to the component / device other. d. hould no one around these tools and plug the barrier and warning signs (that was there megger tests) 3. dangers of megger a. If the cable / busbar are still connected with the components / devices, will result in the components / devices will be damaged b. If the affected person will cause that person will pinsan / death 4. How correct megger test a. Make sure that the participant no 3 above b. Connect terminal E to the cable core (L1) c. Connect terminal L to L2, L3, N and ground d. After connecting all and really like the image below then we turn isulasi test e. We are set in accordance with the capacity of cable that we measure (eg cables for voltages of 400 volt, then isulation test ( megger test ) we set for 1000 volt f. After we finished the settings, press the start button and hold it until 60 seconds g. We just read the results Cable test



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